The Anti-uplift Technology Research Of Shijiazhuang Railway Traffic Underground Structure

With the rapid development of Shijiazhuang’s economy in recent years, traffic jam has become a serious problem, in order to release the traffic pressure, Shijiazhuang has built it’s first subway line—Subway Line One. The durable years of subway line is 100 years. Comparing with the ground structure, once the subway built, it’s very difficult to rebuild.With the development of the South to North Water Diversion Project and people’s water-saving awareness, water table will rise slowly in Shijiazhuang, so in the process of the subway construction, we should pay attention to the unfavorable factors of subway anti floating.When the water table rise slowly in Shijiazhuang, in the process of subway construction, we must take corresponding measures to reduce the water table’s effect on the subway structure. In this paper, we take the Stadium Station of Subway Line One as an example to analysis stress during the rising of water table and how to take appropriate measures to anti floating. During the subway opearion, the commonly used measures are counterweight method, anti floating anchor pile method, uplift pile drop method and composit wall method. By the calculation of anti floating theory and numerical simulation, when the water table rised six metres underground, water the subway structure will lose stability because of table’s buoyancy on the subway structure exceeded the friction force between subway structure weight and it’s surrounding soil. So,in this paper we research on the subway structure displacement and stress when the water table rised eight, six and four metres underground by ANSYS numerical simulation analysis to confirm the appropriate measures to anti floating. then we study respectively the subway structure displacement and stress when the water table rised eight, six and four metres underground. The result of research showed that when water table rised eight, six and four meters underground, the composit wall method is better than other anti floating measures and this method is often used in subway construction of other area.